A Miocene pyrgodesmid millipede (Polydesmida: Pyrgodesmidae) from Mexico.

A new fossil species of pyrgodesmid millipede (Polydesmida: Pyrgodesmidae) placed in the genus Myrmecodesmus Silvestri, 1910 is described. The type materials are two amber inclusions, male and female specimens that come from Miocene strata in Chiapas, Mexico. Myrmecodesmus antiquus sp. nov. has collum with 10 dorsal tubercles; without porosteles or ozopores; legs of the rings 2-9 with a short projection on the prefemur in both the female and male. Myrmecodesmus antiquus sp. nov is the first fossil record of the genus Myrmecodesmus. This is a New World taxon that belongs to the pantropical family Pyrgodesmidae. Thus, Myrmecodesmus antiquus sp. nov expands the range of the genus to the Miocene tropics in Middle America.